Polymer Dosing Rate Calculator
Wastewater & Industrial Water Treatment Optimization
Calculation Results
Required Feed Rate: 0 Liters/Hour
Flow in Milliliters: 0 ml/min
Polymer Consumption: 0 kg/day (Active Polymer)
Pump Stroke/Speed Setting: 0%
Understanding Polymer Dosing Rate Calculations
In wastewater treatment and industrial water purification, polymers (flocculants) are used to aggregate small particles into larger flocs, allowing for easier removal via sedimentation or filtration. Calculating the exact polymer dosing rate is critical for both process efficiency and cost management.
The Polymer Dosing Formula
To determine how fast your dosing pump should run (in Liters per Hour), you need to know three primary factors: the main flow rate of the water being treated, the target dosage in ppm (parts per million), and the strength of the polymer solution you have prepared.
Dosing Rate (L/h) = (Main Flow (m³/h) × Target Dose (mg/L)) / (Solution Concentration (%) × 10)
Note: 1% solution concentration is equivalent to 10 grams of polymer per liter (10,000 mg/L).
Practical Application Example
Imagine a wastewater plant treating 200 m³/h of influent. The laboratory jar test suggests an optimal dosage of 1.5 mg/L. The operator has prepared a 0.2% polymer solution.
- Flow: 200 m³/h
- Dosage: 1.5 mg/L
- Concentration: 0.2%
Calculation: (200 × 1.5) / (0.2 × 10) = 300 / 2 = 150 L/h.
The dosing pump should be set to deliver 150 liters of the prepared solution every hour to maintain the target concentration in the main stream.
Why Precision Matters
Getting the dosage right is a balancing act. Under-dosing results in poor floc formation, cloudy effluent, and potential regulatory non-compliance. Conversely, over-dosing not only wastes expensive chemical resources but can "blind" filter cloths, cause foaming, and actually redisperse particles due to charge reversal.
Tips for Accurate Dosing
- Calibrate Pumps Regularly: Theoretical settings on a pump dial often vary from actual output due to backpressure or wear.
- Monitor Concentration: Ensure the dry polymer is fully hydrated (aged) before use, as undissolved "fish-eyes" effectively lower your solution concentration.
- Check Flow Variations: If your plant flow fluctuates, ensure your dosing pump is linked to a flow meter for automatic adjustment (Pacing).